Universally, without exception, cutter assemblies of the kind having reciprocable sickles have, from the time of first use, been troublesome because of clogging, breakage, wearability, and the failure to provide a proper cutting action. The greatest of the problems has been in maintaining the cutter sections of the sickle in full sliding relationship to the underlying sickle guards such as to assure a scissors-like action in cooperation with the ledger plates on the guards or with the inclined cutting edges of the guards. Heavy grasses, especially when wet, dirt, rocks, and other debris tend to clog the cutter assembly, cause lifting of the sickle sections off the guards as well as breakage of both the sections and the guards.
Hence it has always been necessary to provide some type of clip or hold down in an effort to retain the sickle in place, but no fully satisfactory solution has heretofore been suggested or placed in use. Prior retainers have yieldable characteristics which fail to prevent upward movement of the sickle off the guards and even when they are somewhat satisfactory at the outset, wear on the retainers themselves and on the sickle sections soon results in substantial ineffectiveness.